The invention relates to a circular cross-cut and miter box which comprises a saw assembly including a motor-driven saw blade held on a pivoting arm. The pivoting arm is bearingly supported on a rotatable holder which includes an insertion slit for receiving the saw blade.
Circular cross-cut and miter box saws are known in numerous configurations. German Auslegeschrift No. 1 628 992 shows an embodiment wherein the swiveling saw assembly, which in view of the 180.degree. rotating range of the work table may also be used as a table saw, is mounted on a manually actuated pivoting arm. The bearing support for the pivoting arm is carried by a round table which is rotatably mounted in the rotatable work plate. Circular cross-cut and miter box saws of this type have the advantage that long workpieces may be miter cut by pivoting the round table, without having to alter the support position of the workpiece.
A certain disadvantage of circular cross-cut and miter box saws of this type involves the fact that the cutting range depends exclusively on the size of the saw blade and its depth of immersion, so that for example, boards exceeding a certain width, cannot be processed.
For the processing of wide workpieces table miter saws have already been proposed, e.g., by the Haffner Co., wherein the pivot support for the pivoting arm is located on a longitudinal guide extending parallel to the insertion slit for the saw blade and consisting of a sleeve which slides upon round rods, the rods being fixedly joined to a support table for the workpiece. Such jack saws may also be used as cross-cut saws, but for miter cuts the position of the workpiece on the support table must be altered. A relatively large distance exists between the saw blade and the longitudinal guide. The unavoidable play on the longitudinal guide thus leads to inaccuracies on the workpiece during cutting.
In German Offenlegungsschrift No. 29 29 932 there is disclosed a guide arm which is slidably mounted in a bushing, the latter being fixedly mounted on a rotatable table. The saw housing is fixed to the guide arm whereby the saw can be moved in the direction of the arm as the arm slides within its bushing. In such an arrangement, as in the Haffner Co. saw described above, the saw housing is spaced a relatively long distance from the point where relative longitudinal movement of the guide assembly (i.e., the movement of the guide arm within the bushing). Thus, relative play between the guide arm and the bushing, even if small in itself, will be magnified at the location of the cut due to the long distance of the blade housing from the location of the play.
It is the object of the invention to provide a circular cross-cut and miter box saw of the afore-mentioned type such that the cutting range is enlarged.